The Bornean orangutan (Pongo pygmaeus) is one of only two species of orangutan, which together are the only species of great apes to be found in Asia. Orangutan means 'person of the forest' in the native languages of Indonesia and Malaysia, and orangutans are the largest tree-dwelling mammals in the world. Orangutans have a distinctive body shape, with very long arms that may reach up to two metres in length. They have a coarse, shaggy, reddish coat and grasping hands and feet. The skin of the face is bare and black, but can be pinkish around the eyes and muzzle in younger individuals. Orangutans are highly sexually dimorphic, with adult males being distinguished from females by their larger size. The adult male Bornean orangutan occurs in two forms, flanged or unflanged. Flanged males are larger than unflanged males, and also differ in possessing fleshy, protruding ‘flanges’, or cheek pads, on either side of the face. Flanged males also produce long vocalisations in order to attract receptive females. Bornean orangutans build nests from bent branches high up in the trees where they sleep at night. On average, female orangutans only give birth every eight years, making them the slowest breeding of all mammal species. The diet of the Bornean orangutan includes over 400 different types of food.